PR Copter

Welcome to my copter build page. Right now it's merely a test, but soon here will be lots of useful information.
For now, let's make draft layout.

Preface

Important! On this page I will collect information that will serve as a reference for copter build.
I will be very grateful to any who will help to keep this page up to date with existing changes not distracting core page structure.

Disclaimer

All the information in this manual comes without any warranty and should be used with extreme caution.
Although copters are not too big and heavy machines, significant property damage or harm can be caused by improper use. Be sure to fly in appropriate places, respect people’s privacy and obey and local law restrictions.
If you are unsure with what to do, better double check everything and ask question, than fly unprepared vehicle.

Requirements

Workstation considerations

In my case I was using Ubuntu Linux 32 bit for firmware builds and upgrade. On windows version of update software I was not able to flush firmware getting “Unable to open port” on all my systems. Well, maybe it will change with time.
Now, what we’ll need:

Buzzer – connects to PX4FMU board and gives audial feedback on system working modes. I guess it might also warn on some critical inflight conditions, like battery depletion. Mandatory.

Arming switch (with red led inside) – connects to PX4FMU module and arms it. Also indicates current system arming state by various blinkings. Mandatory with PX4IO.

6. Wires: In my case it took: - one 5pin wire to connect PX4IO to PX4FLOW and - one 9pin wire to hook up to PX4FMU USART1 for console. (Note, that connector less than 9pin won’t allow you to match required pin width. If you are going to order connectors at store, I’d rather recommend full length 15pin connector {http://store.diydrones.com/DF13_15_Position_Connector_p/ca-0001-44.htm} ).

Now, the “flying stuff”:

You’ll need 4 to 8 ESC’s depending on your copter layout. Please keep in mind, that standalone PX4FMU unit can handle only up to 6 rotors. PX4IO allows using 8 rotors. For my experiments I’ve used Turnigy Plush 6A ESC’s for they are 400Hz PWM capable.

Then you’ll have to get the same amount of motors. i.e. for quadrotor you need 4 esc’s and 4 motors.

Also you can not do anything without RC Receiver. In my case I’ve used FrSky TFR4 in CPPM mode.

Misc things like copter frame and battery are also needed.

Airframe construction and it's caveats

It is important to understand, what kind of vehicle you want to get as a result. Currently there are two types of airframes supported: (as soon as it is not manual, I'll just place links sometimes) Multicopters

PX4 Hardware specific information

In this section I will give only information that is important and sometimes mission-critical for copter function.

PX4FMU

Basically it's brain of the system.

At this point all system settings are stored in flash memory of CPU. See software section for detailed configuration process.

The following table shows port distribution on FMU board.

NuttX UART

PX4FMU UART

PX4IO UART

desc

ttyS0

UART1

USART1

Free port, can be used for various tasks

ttyS1

UART2

MavLink

MavLink port for telemetry and control

ttyS2

UART5

PX4FLOW

PX4FLOW module uplink port (optional)

ttyS3

UART6

GPS

GPS receiver uplink port (optional)

PX4IO

Port extension and power source board.

Board power source is pretty noisy, so try to keep it away from magnetometer.

PX4FLOW

Optical flow module. Something from far-far space. Not working tip-top just yet.